Human Heart

Your heart is located in the upper left-hand side of your chest and if you place your hand there, you can feel it beating. The heart continually pumps blood to all parts of the body, and never stops beating, even when you are asleep. Because of its importance, many complex surgeries (and even artificial hearts) have been developed to keep one’s heart going thump, thump, thump.

Wow! During your lifetime, your heart will beat two and a half billion times without stopping to rest. This site provides information about what the human heart is, and how it grows and develops. It also explains the structure of the heart, with images and diagrams. There are activities for the classroom, index cards, images, and links to additional reading about the heart. "Like a pumping machine, the heart provides the power needed for life. This life-sustaining power has, throughout time, caused an air of mystery to surround the heart."

Point and click your way around this interactive heart diagram from InnerBody that introduces the parts of the heart and their functions. "Internally, the heart is divided into four hollow chambers, two on the left and two on the right. The upper chambers, called 'atria,' have relatively thin walls and receive blood returning through the veins." Visit to learn more about chambers, ventricles, valves, veins and how they all connect.

"Did you give your friends valentines and little heart-shaped candies on Valentine's Day? Do you ever cross your heart when making a promise that you really, really mean? Or turn on the radio to hear a guy singing about his broken heart?" KidsHealth explains that your heart isn't your emotional center and doesn't make you fall in love. The heart is a tireless muscle pumping blood to your organs. And without it, your other organs wouldn't get the oxygen or energy they need to do their job.

"Your heart is about the same size as your fist and weighs a little less than two baseballs." This interactive website takes you step-by-step through an exploration of the heart, along with tips on making heart-healthy food choices. Fun sounds and graphics make this perfect for elementary grades. When the exploration is completed, you earn a certificate to save or print.

WebMD's detailed picture shows exactly what your heart looks like, and it's nothing like what you see on a Valentine's Day card! Learn all about heart defects and diseases, from serious ones like heart attacks (and coronary artery disease) to less serious ones like heart murmurs. In addition to the anatomy lessons, there is plenty of heart-healthy advice with articles such as 24 Foods that can Save Your Heart and 15 Steps to Lower Cholesterol.